Rechargeable battery pack



FIG. 1 is a front elevational view of a rechargeable battery pack showing our new design;

FIG. 2 is a right side elevational view thereof; the left side being a mirror image of the right side;

FIG. 3 is a back elevational view thereof;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a rechargeable battery pack, as shown and described. 